Head Trauma Linked To Alzheimer's Disease

Researchers at the University of Pennsylvania in Philadelphia are working to find out more about Alzheimer's Disease. The findings back previous studies that suggested brain trauma increases the risk of Alzheimer's disease, a leading cause of dementia, later in life. Trauma to the head may trigger a cascade of biochemical events in the brain, in time resulting in neurodegenerative changes similar to those found in patients with Alzheimer's disease. Dr. Douglas Smith says his findings support "several epidemiologic reports (that have suggested) a link between a single episode of brain trauma and the development of Alzheimer's disease later in life." Smith's team induced brain injury in anesthetized pigs via very rapid acceleration/deceleration of the animals' heads without direct impact, similar to what humans often experience in an automobile accident. Brain trauma is one of the only environmental risk factor for Alzheimer's disease, so there is something about brain trauma that might initiate these insidious neurodegenerative cascades. The analyses of the brain tissue revealed a remarkable and consistent accumulation of amyloid beta and tau proteins in damaged brain cells following trauma. In Alzheimer's disease, changes in tau protein lead to the disintegration of microtubules in brain cells disintegrating the neuron's transport system for nutrients. In the study animals, these changes were evident as early as 3 to 10 days post-injury. The team concluded that microscopic injury to the brain caused by trauma can be linked to the development of Alzheimer's disease many years after the injury. The findings may also lead to new drugs aimed at preventing the process. "This study adds to the body of knowledge that might aid us in the development of an anti-plaque-making compound," Smith said in a statement.